American Airlines is threatening to take its pilots’ union to court. It’s accusing the pilots of disrupting flights with sickouts, and by calling for unnecessary maintenance that delays flights.

American is in bankruptcy protection, trying to restructure. It’s trying to impose new pay and work rules on its pilots -- and they’re not happy. Their union hasn’t called for any official action, but American says pilots are filing more maintenance complaints and flying circuitous routes.

Seth Kaplan is managing partner at Airline Weekly magazine. He thinks all the delays aren’t just coincidence. “You don’t suddenly have far more people getting sick at the same time, far more mechanical issues," he says. "Something organized is going on.”

The union says it’s not fair that American is using bankruptcy protection to impose pay cuts, and that the problems are due to old planes and a pilot shortage. But American says the percentage of pilots calling in sick has increased at least 20 percent a month.

Airline analyst Richard Aboulafia says part of the problem is it took so long for American to file for bankruptcy protection. Now its competitors have reorganized and merged, and American is still struggling.

“What American is doing now is basically playing catch up," Aboulafia says, "and trying to get its costs in line with its competitors before it loses even more market share.”

That’s a real possibility. American has had many more cancelled and late flights than its competitors, and its passengers aren’t happy.